Just what are you inhaling during your rush hour commute?

For those of you who routinely cycle on roads, you will know how awful it is when a car in front of you accelerates and leaves you in a smoky cloud of exhaust fumes. In Singapore (and many other Southeast Asian countries) the worst culprit are motorcycles. Their exhaust systems seem to create smellier and blacker smoke than cars. Same goes for the mid-sized trucks that ferry around construction workers. These ones, I suspect run on diesel.

To give you an idea of my commute: I live in the ‘suburbs’ of Singapore. I cycle almost every weekday to work, a 4.5km route that splits evenly between a bike path that runs along a river and on two four-lane roads. I generally cycle to work at 6:15am and back in the evening. It takes me about 15mins each way, depending the weather and my luck with the seven traffic lights. The commute to work in on a slight incline. I’d say that my commute is considered fairly short and the exposure to car exhaust low.

To give you an idea of pollution in Singapore: car traffic is similar to any large city in Canada, for example, Toronto and Montreal. However, there are more motorcycles and construction-related vehicles. On average I would say about 5 of each would pass me on my commute to work. There would be more on the way from work, as it would be rush hour.

I decided to start using a mask for several reasons.

• I realized that I started to hold my breath every time a motorcycle accelerated in front of me
• I inhaled several tiny, black flies after cycling through swarms on them by the river on several occasions
• Exhaust from buses gave off a white smoke and peculiar chemical smell that I didn’t like
• I noticed how much black dust accumulated on my bike and tires from riding on the road
• Singapore and Malaysia were struck with a dense haze from forest fires in Sumatra

I wanted to reduce the amount of dust and I was inhaling while on the road and keep the little flies out of my mouth. I also wanted to make the exhaust and haze bearable in terms of smell. Another practical aspect is simple that it’s easier to cycle without choking or having to hold my breath.

And this is what it looked like after 2 months. You can see that even though I have a short commute with lower exposure to car exhaust the filters are clearly blackened. Can you imagine what this filter would look like if commuting for a longer distance in an urban setting? This stuff could be in your lungs.

Why specifically an anti-pollution mask?

In Southeast Asia, I’ve seen people use all kinds of things to cover their nose and mouth – Buff, bandannas, silk scarves, the collar of their shirt, surgical masks etc. All of them are better than nothing but the problem is that many of the materials are too porous and fail to properly filter out tiny particulates and you end up breathing them into your lungs.

Anti-pollution masks not only filters out very small particulate matters, they also filter chemicals produced by car combustion like nitrogen oxides, benzene, sulphur dioxide etc.

The Importance of Particulate Matter (PM) Size

Particles in the air consists of a very wide range of materials in various forms – dry solid material, liquid-coated solid material and small droplets. They are measured in microns. Material that is 10 microns (PM10) in size starts to cause health concerns as the particles can be inhaled and trapped in the mucus membrane in your nose and back of the throat, causing irritation and inflammation. Smaller particles at 2.5 microns (PM2.5) are small enough to be inhaled into the lungs and enter the bloodstream, affecting the heart, blood vessels and of course, the lungs. Thus, these very small particles are the most dangerous. The following diagram from the California Environmental Protection Agency does a pretty good job with explaining the size of particulate matter:

http://www.arb.ca.gov/research/aaqs/pm/pm.htm

The common comparison used is the cross section of the piece of hair. PM10 is approximately seven times smaller in diameter than the hair cross section. PM2.5 is about four times smaller than PM10 so you can imagine how easy it is for people to inhale such small particles.

What Kind of Things Am I Breathing In When I Cycle?

Ok so now we know of the very small particulate matter we can breathe in but it’s what it’s made of that’s the most important. Here’s what I feel are the most important to me:

• Car combustion and its by-products
• Industrial air pollution from factories and power plants (more combustion, actually)
• Forest fire smoke
• Pollen

The main culprit here is the burning of fuel (combustion), be it fossil fuels or forests. The main pollutants that are dangerous are carbon monoxide, nitrogen dioxide, sulphur dioxide (gases) and particulates that make up smoke. See here for further info from this factsheet from the University of Utah.

Combustion pollutants can cause headaches, dizziness, nausea, throat and eye irritation and respiratory problems. And there are lesser, but equally noxious substances like benzene (used in car fuel) and asbestos (used in brake linings).

And of course, if you have allergies, inhaling pollen would be a concern as you zip around the outdoors.

Why Not a Surgical Mask? 

Surgical mask or cotton masks are not good candidates because they are not design for airborne particulates. Cottom is too porous and surgical masks are leaky. However, I’ve tried wearing NIOSH N95 masks on my commute but I found their fit difficult to adjust on the fly and leaked as a result. The masks that have two separate straps around the entirety of the head fits better than just one strap or the masks that hook behind the ears (worst).

The masks generally don’t have exhalation valves and it can be difficult to get enough air on a steep climb. The masks can really soak up sweat when it’s the kind that touches your chin, nose and lips. However, surgical masks are cheaper and it’s better than nothing. But make sure they certified (N95) to filter out the bad stuff.

Alright, What Mask Should I Get?

I knew I could convince you! There’s two that I suggest you check out: Respro (I have this) and Totobobo (I haven’t tried this). Allow me to make arguments and counter-arguments for each one (Yes, even the one I didn’t try):

RESPRO (I have the Techno mask)

• Filters out harmful gases and particulate matter
• Available in several sizes
• Fabric shell (comfy)
• Exhalation valves
• Reusable shell (change the filter only)
• Cool shell design for those who want to be stylin’
• Fairly long lasting (I used mine for two months!)

Problem

• Only medium and large for Techno (leaks under chin sometimes so I have to be careful how I put it on)
• Very hot when wearing in Singapore (shell made of neoprene)
• Not see through (I can look rather threatening and mysterious/people can’t see your face)
• Kinda expensive (42CAD – 45SGDish for mask and two filters. More expensive if you buy it in Singapore. Sorry!) Replacement filters run about 12 bucks apiece.

Totobobo (My friend’s mask)

• Filters out viruses (so they say) and particulate/gases
• Endlessly adjustable (They advise you on how to cut the plastic shell to perfect fit, even cover the mouth only)
• People can see your face
• Your face doesn’t touch the filter (ick factor)
• Small filters on each side
• Two rather invisible and thin head straps (minimalistic)
• Visible water seal for checking airtight fit
• Reusable shell

Problem

• No exhalation valves (more difficult to breath)
• Plastic-y (My own opinion, I don’t like the feeling of plastic on my face)
• Kinda expensive (33USD for the mask, the replacement filters are cheaper than Respro but don’t last as long)

So there you have it. I suggest that you research and test out your own preference of course because you need to make up your own mind on what’s best for you health. I am no doctor of course so this is not expert advise by an stretch of the imagination, just my experience. Here are the two companies’ websites:

Respro – http://respro.com/pollution-masks

U-Mask – http://www.u-maskstore.eu/#_l_4p

Totobobo – http://totobobo.com/buy.html

Also, here are several websites I found very insightful when researching about air pollution:

My Health Beijing – this doctor does a mind boggling amount of research on pollution masks, check out his other articles as well on the right side

World Air Quality Index – Great summaries of masks and excellent infographics

Hope you keep your lungs safe and happy cycling!